Web folding machine

ABSTRACT

A machine for making accordion-like folds in a web having a curved table on which successive folded layers of the web are received and having a pair of spaced clamps overlying the edges of the table. A web guide overlies the table and is oscillated between the clamps in a curved path generally similar to the curvature of the table and is simultaneously rotated to form loops in the web which are tucked under a raised clamp which is lowered to retain the loop thereunder and form a sharp straight unwrinkled crease or fold therein.

United States Patent [191 Klepper et al.

[451 Sept. 17, 1974 WEB FOLDING MACHINE [75] Inventors: Constant L. Klepper; Ronald Koziel,

both of Troy, Mich.

[73] Assignee: Klep Corp., Madison Heights, Mich.

22 Filed: Oct. 16,1972

21 Appl. No.: 297,718

52 U.S.Cl. 270/79, 270/30, 270/61 F 51 Int. Cl ..B65h 45/20 [58] Field ofSearch 270/79, 78, 30-31,

270/73, 61 F; 269/157, 254 CS, 162, 188, 224; 72/315; 74/582 [56] References Cited UNITED STATES PATENTS 592,264 10/1897 Wadsworth 270/79 3,375,777 4/1968 Techtmann et al 74/582 FOREIGN PATENTS OR APPLICATIONS 59,882 3/1912 Switzerland 270/79 521 3/1854 GreatBritain ..270/79 81,583 11/1894 Germany ..270/79 Primary Examiner-Harland S. Skogquist Assistant Examiner-A. Heinz Attorney, Agent, or Firm-Barnes, Kisselle, Raisch & Choate [5 7] ABSTRACT A machine for making accordion-like folds in a web having a curved table on which successive folded layers of the web are received and having a pair of spaced clamps overlying the edges of the table. A web guide overlies the table and is oscillated between the clamps in a curved path generally similar to the curvature of the table and is simultaneously rotated to form loops in the web which are tucked under a raised clamp which is lowered to retain the loop thereunder and form a sharp straight unwrinkled crease or fold therein.

3 Claims, 8 Drawing Figures PAIENTED SEP 1 71914 SHEET 2 OF 4 WEB FOLDING MACHINE This invention relates to machines for making accordion-like folds in a web and, more particularly, to a blueprint folding machine.

Various types of devices have been provided heretofore for folding web material, such as cloth or paper, in accordion pleated fashion. However, from the practical standpoint, such prior art devices have one or more shortcomings. For example, some are of very complicated construction; others are not designed to produce accurately aligned creases or folds; still others are large and cumbersome while others are not completely auto matic. Furthermore, some of such devices are suitable for use in folding fabric material but not for folding paper web which in most instances has considerably less tensile strength than most fabrics.

The present invention has for its primary object the provision of a machine for automatically folding blueprint paper webs which is of simple and economical construction, which is adapted to produce sharp accurately aligned creases or folds, and which does not have the tendency to tear, rip or wrinkle the paper web.

More specifically, the present invention comprises a blueprint folding machine having an arcuate paper support surface with a pair of articulated spring clamps adjacent opposite ends thereof and a paper web guide oscillatible between the clamps in a path generally parallel to the curved surface of the paper support. The web guide includes a pair of parallel spaced guide bars which in response to oscillation of the web guide revolve through an arc of about 180 in a manner such as to fold and tuck the paper web under the two clamps.

These and other objects, features and advantages of this invention will be apparent from the accompanying description, appended claims and drawings in which:

FIG. 1 is an isometric view of a blueprint folding machine embodying this invention;

FIG. 2 is a view of one end of the blueprint folding machine with its associated end cover removed;

FIG. 3 is a generally longitudinal sectional view of the blueprint folding machine;

FIG. 4 is a sectional view on line 4-4 of FIG. 3 with the web guide at one end of its stroke;

FIG. 5 is a view of the other end of the blueprint folding machine with its associated end cover removed; and

FIGS. 6, 7 and 8 are fragmentary isometric views of the web guide and drive mechanism of the blueprint folding machine.

Referring in more detail to the drawings, FIGS. 1, 3 and 4 illustrate a blueprint folding machine 10 embodying this invention with a web guide generally designated 12 overlying a curved table 14 and a pair of spaced clamps 16 and 16 extending generally axially of table 14 adjacent the free edges thereof. A frame for machine 10 is provided by generally opposed upright end plates 18 and 20 (FIG. 3) retained in fixed laterally spaced relation by a pair of tie rods 22 which extend through and beyond the end plates and are secured thereto by jam nuts 24. End covers 28 and 30 overlie end plates 18 and 20 and are retained in place by acorn nuts 32 on the ends of tie rods 22. End filler plates 34 having arcuate slots 36 providing clearance for web guide 12 are secured to the upper edges of end plates 18, 20 by screws 38. The mechanism between the end plates is enclosed at the top by curved table 14 and at the sides and bottom by a pan 40 having tabs 42 secured to end plates 18, 20 by cap screws 44 and 45, respectively, as shown in FIGS. 4 and 5.

As shown in FIGS. 1,3 and 6, web guide 12 includes two laterally spaced parallel rods 46, 46 with smooth cylindrical outer surfaces and with their free ends fixedly received in cross links 48. Web guide 12 is mounted for oscillation between clamping members 16, 16 by carrier arms 50 and 52 and for rotation on a longitudinal axis centered between rods 46 by stub shafts 54 (FIGS. 3 and 6). At one end stub shafts 54 are received in holes 56 of links 48 and secured therein by set screws 58. The opposite ends of stub shafts 54 are retained in sleeve bearings 60 at the upper ends of carrier arms 50, 52 (FIG. 6). Carrier arms 50, 52 are radially aligned in opposed relation on the opposite ends of a horizontally extending rocker shaft 62 by transverse pins 64. The lower end of each carrier arm 50 and 52 is split and clamped on rocker shaft 62 by a bolt and lock nut assembly (as shown in FIGS. 7 and 8). Rocker shaft 62 is mounted for rotation in end plates 18, 20 by bushings 74 and is prevented from shifting axially by collars 76 secured to rocker shaft 62 on opposite sides of end plate 20 by set screws 78. The axis of rotation of shaft 62 preferably coincides with the axis about which the curvature of table 14 is generated. In any event, it is desirable that the web guide be caused to traverse an arcuate path at least similar to the curvature of table 14.

As shown in FIGS. 3 and 7, web guide 12 is driven by an electric motor 82 mounted on end plate 20 by screws 84 and operably connected to carrier arm 52 by a crank 86 and a link 88. One end of crank 86 is fixed to a drive shaft 90 of motor 82 and its other end is pivotally connected to one end of link 88 by a stud 94. The other end of link 88 is pivotally connected to a laterally offset extension 99 of carrier arm 52 by a stud and retainer nut assembly 100.

Web guide 12 is rotated about the axis of stub shafts 54 when oscillated between clamp members l6, 16 by a drive gear 106 on the stub shaft journalled at the upper end of arm 50 and a stationary gear 108 interconnected by a timing belt 110. Stationary gear 108 is fixedly mounted on end plate 18 concentric with carrier shaft 62 by a cap screw 118 and a spacer 120.

As shown in FIGS. 1 and 3, each clamp 16, 16 has a longitudinally extending shoe 122 formed as an extrusion with a return bend hook 124 adjacent its rear edge by means of which it is pivotally supported on a rod 128. At each end rods 128 are journalled in selfaligning bearings 130 fixedly received in end filler plates 34. Each shoe 122 has a generally upturned leading edge 132 and a recess 134 in its lower face fixedly receiving therein a longitudinally extending neoprene pad 136. I

As shown in FIGS. 3 and 4, clamps 16, 16 are operably connected to shaft 62 by two pairs of springs 138 and 140 and two pairs of crank arms 142 and 144 fixed to the rocker shaft. The radially outer end of each spring 138, 140 is pivotally connected to an integral tab 146 of its associated clamp 16, 16 as at 148 (FIG. 4) and the inner end of each spring is connected to the distal end of its associated crank 142, 144 by a cotter key To facilitate the feeding of a web of blueprinted paper 168 directly from a blueprint machine into folding device 10, a guide roller 152 is mounted adjacent a lower edge of folding device below and preferably slightly outboard of the adjacent free edge of curved table 14. Guide roller 152 is preferably formed as a hollow tube 154 having ball bearings 156 fixedly received in -'he opposed ends thereof. Guide roller 152 is journailed for free rotation on a pair of stub shafts 160 fixedly received in holes 162 in end plates 18 and and in the inner races 164 of bearings 156. A web guide disc, 166 is fixed adjacent one end of roller 152 and a web guide disc 166 is adjustable axially on roller 152 to accommodate different width paper webs.

In using blueprint folding device 10 the motor is energized to-initially locate web guide 12 at about its mid position shown in broken lines in FIG. 4 while travelling in the direction toward clamp 16 as indicated by arrows 172. Thereafter the leading end 170 of paper web 168 is threaded preferably under folding device 10 between end plates 18, 20, upwardly around guide roller 152, over rod 46 and under rod 46 of web guide 12 and thence is inserted under clamp 16. Web 168 is preferably threaded under folding device 10 and around guide roller 152 in the manner described so that the web can be folded as it emerges from a blueprint machine located to the right of the folding machine as shown in FIG. 4. With the web guide initially positioned as described, the leading end 170 of web 168 is inserted under clamp 16 by manually raising the clamp against the bias of its springs 140.

After web 168 is threaded into folding machine 10 as described motor 82 is energized which oscillates and simultaneously rotates web guide 12 to form a loop in web 168 and tuck it under clamp 16 or 16 during each traverse of the web guide. Motor 82 drives crank 86 to pivotally rock carrier arms 50, 52 on shaft 62 and thereby oscillate web guide 12. When web guide- 12 is traversing counterclockwise (as viewed in FIG. 4), the web guide is rotated clockwise about stub shafts 54 substantially half a revolution to form a loop in web 168, around rod 46 and tuck it under clamp 16. Conversely when web guide 12 is traversing clockwise it is rotated counterclockwise substantially half a revolution to form a loop in web 168, around rod 46' and tuck it under clamp 16'. Web guide 12 is rotated to form the loops in web 168 by timing belt 110 and gears 106 and 108 in response to oscillation of the web guide. Since in folding device 10 as shown and described, web guide 12 traverses through an arc of 90 or a quarter of a revolution and the web guide rotates substantially half a revolution during each traverse to form a loop in the web to be tucked under a clamp, gears 106 and 108 are selected so that they have a 1:2 ratio.

Clamps 16, 16 are moved to clamping and releasing positions in synchronization with the traversing movement of web guide 12 to allow rods 46, 46 of the web guide with a loop of web 168 thereon to pass under each clamp, retain the loop under the clamp and fold the loop with a sharp straight crease. When rocker shaft 62 and, thus, web guide 12 is rotated clockwise (as viewed in FIG. 4) cranks 142 elongate and tension springs 138, which firmly urge clamp 16 toward curved table 14 and into clamping position. Simultaneously, this clockwise rotation of rocker shaft 62 causes cranks 144 to foreshorten and completely relieve the'tension in springs 140 to pivot clamp 16 away from curved table 14 and into releasing position. Similarly, counterclockwise rotation of rocker shaft 62 elongates springs 140 and foreshortens springs 138 to pivot clamp 16' to the clamping position adjacent curved table 14 and clamp 16 to the releasing position away from curved table 14. Hence, each clamp 16, 16 is raised as web guide 12 approaches the clamp to allow rods 46, 46, respectively, with a loop of web 168 formed thereon, to pass under the clamp and is pivoted toward the clamping position to retain the loop under the clamp by frictional engagement with the neoprene pad 136 thereof as the web guide traverses in the opposite direction and to form a sharp straight crease or fold in the loop. Web guide 12 is traversed and rotated by motor 82 until all of web 168 is folded and, then, the motor is shut off and the folded web removed by manually raising the clamps.

Preferably springs 138, 140 function essentially as rigid push rods when moving clamps 16, 16' to the fully released position. This is preferably achieved by using springs wound so that their coils abut each other when the springs are in a free state, with the springs being of an appropriate length so that their coils are urged into abutting relation during the final portion of the rotation of rocker shaft 62 to pivot the clamps associated with the springs to the released position. Alternatively, springs 138, 140 will function essentially as rigid push rods if their spring rate is large enough so that the springs are not substantially compressed when transmitting sufficient force to their associated clamps to overcome the inertia thereof and move the clamps to the release position.

The arrangement of cranks 142, 144 on rocker shaft 62 so that the axes of springs 138, 140 crisscross each other in the manner shown in FIG. 4 and apply opposed moments to the rocker shaft allows a low torque motor 82 to be used in driving folding machine 10 by decreasing the peak torque demand on the motor. This crank and crisscross spring arrangement also improves the effectiveness of clamps 16, 16' in retaining and folding a loop of web 168 thereunder immediately upon the initial movement of web guide 12 in withdrawing rods 46, 46 from under the clamps. The crank and crisscross spring arrangement during initial rotation of rocker shaft 62 to withdraw web guide 12 from under a clamp provides a substantially greater axial displacement of the foreshortened springs holding the clamp in the releasing position than of the elongated spring urging the other clamp into the clamping position. More specifically, as shaft 62 starts to rotate in a counterclockwise direction from the position shown in FIG. 4, the cranks 142, 144 are arranged such that springs 140 are foreshortened at a faster rate than springs 138 are relieved. Thus, this crisscross spring arrangement during initial withdrawal of web guide 12 from under 21 released clamp creates a substantial force urging the released clamp toward the clamping position and the neoprene pad 136 into firm frictional engagement with the loop while only slightly decreasing from its maximum the force urging the other clamp into clamping position. Hence this crank and crisscross spring arrangement provides a non-linear displacement ratio of springs 138 and 140 resulting in a non-linear application of force to the clamps. This improves the effectiveness of clamps 16, 16' in retaining and folding a loop of the web thereunder. Thus, preferably the included angle between the longitudinal center lines of cranks 142, 144 is not substantially greater, and preferably slightly less, than and the cranks are angularly oriented on rocker shaft 62 so that each crank extends generally vertically when its associated clamp is in the released position. Furthermore, the cranks are preferably arranged so that a line extending through stub shafts 54 and rocker shaft 62 substantially bisects the included angle between the cranks. Securing cranks 142, 144 to rocker shaft 62 at an included angle of approximately 87 to 90 has proved highly satisfactory because it retains the advantages of the crisscross arrangement while assuring that the clamps 16, 16 are moved to the releasing position just prior to rod 46, 46, respectively, of web guide 12 passing under the clamps as shown in phantom in FIG. 4. This improves the folding action of the clamps and the uniformity of the spacing between the folds.

The length of carrier arms 50, 52 and the spacing of rods 46, 46' from stub shaft 54 are predetermined such that, when the carrier arms reach the opposite ends of their oscillating stroke, the bottom surface of the lower rod is spaced a predetermined distance above the underlying curved surface of table 14. With a clearance, for example, of about one-eighth inch a paper web about 20 feet long can be folded with accordion pleats of about 12 inches in width. A predetermined clearance between the rods and the table is important since springs 140 act as rigid links of fixed length to pivot clamps 16, 16' to a predetermined open position and it is desired for optimum efficiency that the paper web around rods 46, 46 be engaged by the neoprene pads 136 as soon as the web guide reaches either end of its stroke regardless of the number of underlying folds which have already been completed. This assures folding the successive pleats of the paper web at a consistently uniform width and also provides clearance between rods 46, 46 of the web guide and the underlying top layer of the folded web on the curved surface of the table 14 which prevents scuffing of the folded top layer of the web. The arrangement of the single drive motor 82 for simultaneously oscillating web guide 12 through rocker shaft 62 and rotating the web guide by timing belt 110 and timing gears 106, 108 while synchronously raising and lowering the clamps through springs which preferably function as rigid push rods in raising the clamps provides a folding device of simplified design with a minimum number of component parts, which is of economical manufacture and assembly and is maintenance and service free.

We claim:

1. A machine for folding a continuous length of web material transversely of its length in accordian-like fashion to form'said web into a plurality of stacked plies of substantially uniform width with each ply connected by a fold line at its opposite ends with the next adjacent plies, comprising a support having a curved web support surface defined generally as a segment of a circular cylinder, said support having a pair of clamps thereon disposed adjacent said surface and spaced circumferentially apart thereon to correspond generally with the desired width of said plies between the opposite fold lines, means for alternately actuating said clamps to clamped and released positions. said clamps in the clamped position being biased toward said support surface to engage the underlying plies on said support surface adjacent said fold lines, a pair of arms mounted on said support, one at each side of said curved support surface,.for pivotal movement about an axis parallel to the axis of said cylinder and disposed generally centrally between said clamps and radially inwardly of said support surface, said arms extending radially outwardly beyond said curved support surface, means for pivotally oscillating said arms in unison so that their outer ends traverse an arcuate stroke which extends over said curved surface and terminates at each end adjacent the two clamps, a web guide supported by and connecting the free ends of said arms, said web guide comprising a pair of laterally spaced, elongated guide members extending transversely across said support surface and parallel to the axis of said cylinder, a pair of elongated linking plates connected at their opposite ends with the opposite ends of said guide members so that the guide members and linking plates form a generally rectangular open frame, said linking plates being pivotally connected centrally between the ends thereof, one with the outer end of each of said arms so that the web guide is rotatable on the outer ends of said arms about an axis spaced from and parallel to the pivotal axis of said arms, a first drive gear on said support fixedly and non-rotatably mounted thereon with its center coinciding with the pivot axis of said arms, a second drive gear fixed on said web guide at the pivot axis thereof, drive means extending between and forming a driving connection between said first and second drive gears for rotating the second drive gear and said web guide as a unit in opposite directions in response to the swinging movement of said arms in opposite directions about the center of said fixed drive gear, said two drive gears and said drive means being adapted to rotate said web guide in opposite directions such that one of said guide members is disposed adjacent said curved surface as the arms approach one end of their stroke adjacent one of said clamps and the other of said guide members is disposed adjacent said curved surface as the arms approach the other end of their stroke adjacent the other clamp and means for operating said clamp actuating means in timed relation to the oscillation of said arms such that each clamp is actuated to the released position as the arms approach the clamp and is actuated to the clamped position as the arms reach one end of their stroke adjacent the clamp and swing in a direction toward the other clamp.

2. The combination called for in claim 1 wherein said arms are pivotally mounted on said support at the axis of said cylinder.

3. The combination called for in claim 1 wherein said means forming a driving connection between said first and second drive gears comprises an endless drive element trained around and engaging said gears. 

1. A machine for folding a continuous length of web material transversely of its length in accordian-like fashion to form said web into a plurality of stacked plies of substantially uniform width with each ply connected by a fold line at its opposite ends with the next adjacent plies, comprising a support having a curved web support surface defined generally as a segment of a circular cylinder, said support having a pair of clamps thereon disposed adjacent said surface and spaced circumferentially apart thereon to correspond generally with the desired width of said plies between the opposite fold lines, means for alternately actuating said clamps to clamped and released positions, said clamps in the clamped position being biased toward said support surface to engage the underlying plies on said support surface adjacent said fold lines, a pair of arms mounted on said support, one at each side of said curved support surface, for pivotal movement about an axis parallel to the axis of said cylinder and disposed generally centrally between said clamps and radially inwardly of said support surface, said arms extending radially outwardly beyond said curved support surface, means for pivotally oscillating said arms in unison so that their outer ends traverse an arcuate stroke which extends over said curved surface and terminates at each end adjacent the two clamps, a web guide supported by and connecting the free ends of said arms, said web guide comprising a pair of laterally spaced, elongated guide members extending transversely across said support surface and parallel to the axis of said cylinder, a pair of elongated linking plates connected at their opposite ends with the opposite ends of said guide members so that the guide members and linking plates form a generally rectangular open frame, said linking plates being pivotally connected centrally between the ends thereof, one with the outer end of each of said arms so that the web guide is rotatable on the outer ends of said arms about an axis spaced from and parallel to the pivotal axis of said arms, a first drive gear on said support fixedly and non-rotatably mounted thereon with its center coinciding with the pivot axis of said arms, a second drive gear fixed on said web guide at the pivot axis thereof, drive means extending between and formIng a driving connection between said first and second drive gears for rotating the second drive gear and said web guide as a unit in opposite directions in response to the swinging movement of said arms in opposite directions about the center of said fixed drive gear, said two drive gears and said drive means being adapted to rotate said web guide in opposite directions such that one of said guide members is disposed adjacent said curved surface as the arms approach one end of their stroke adjacent one of said clamps and the other of said guide members is disposed adjacent said curved surface as the arms approach the other end of their stroke adjacent the other clamp and means for operating said clamp actuating means in timed relation to the oscillation of said arms such that each clamp is actuated to the released position as the arms approach the clamp and is actuated to the clamped position as the arms reach one end of their stroke adjacent the clamp and swing in a direction toward the other clamp.
 2. The combination called for in claim 1 wherein said arms are pivotally mounted on said support at the axis of said cylinder.
 3. The combination called for in claim 1 wherein said means forming a driving connection between said first and second drive gears comprises an endless drive element trained around and engaging said gears. 